In many audio applications, audio signals are recorded. For example, in a frequency modulation (FM) recording application in mobile phones, tablet computers, or other portable devices, FM programs can be recorded in response to user operations on recording buttons or based on a reservation. Recorded audio signals may include a mixture of song, speech (including speech-over-music), noise, silence, etc. Users may desire to only save individual songs in the recorded audio signals.
An approach has been proposed to detect songs from audio signals based on repeating occurrences of audio segments in the audio signals, assuming that a repeated long audio segment is a song while speech seldom repeats for multiple times. An example implementation of the approach can be found in PopCatcher Internet Radio Recorder Application from PopCatcher AB, Hastholmsvagen 28, 5tr, 131 40 Nacka, SWEDEN, which is herein incorporated by reference for all purposes.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section Similarly, issues identified with respect to one or more approaches should not assume to have been recognized in any prior art on the basis of this section, unless otherwise indicated.